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Concept: Pomegranate

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BACKGROUND: This study evaluated, using in vitro assays, the antibacterial, antioxidant, and tyrosinase-inhibition activities of methanolic extracts from peels of seven commercially grown pomegranate cultivars. METHODS: Antibacterial activity was tested on Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Klebsiella pneumonia) using a microdilution method. Several potential antioxidant activities, including radical-scavenging ability (RSA), ferrous ion chelating (FIC) and ferric ion reducing antioxidant power (FRAP), were evaluated. Tyrosinase enzyme inhibition was investigated against monophenolase (tyrosine) and diphenolase (DOPA), with arbutin and kojic acid as positive controls. Furthermore, phenolic contents including total flavonoid content (TFC), gallotannin content (GTC) and total anthocyanin content (TAC) were determined using colourimetric methods. HPLC-ESI/MSn analysis of phenolic composition of methanolic extracts was also performed. RESULTS: Methanolic peel extracts showed strong broad-spectrum activity against Gram-positive and Gram-negative bacteria, with the minimum inhibitory concentrations (MIC) ranging from 0.2 to 0.78 mg/ml. At the highest concentration tested (1000 mug/ml), radical scavenging activities were significantly higher in Arakta (83.54%), Ganesh (83.56%), and Ruby (83.34%) cultivars (P< 0.05). Dose dependent FIC and FRAP activities were exhibited by all the peel extracts. All extracts also exhibited high inhibition (>50%) against monophenolase and diphenolase activities at the highest screening concentration. The most active peel extract was the Bhagwa cultivar against monophenolase and the Arakta cultivar against diphenolase with IC50 values of 3.66 mug/ml and 15.88 mug/ml, respectively. High amounts of phenolic compounds were found in peel extracts with the highest and lowest total phenolic contents of 295.5 (Ganesh) and 179.3 mg/g dry extract (Molla de Elche), respectively. Catechin, epicatechin, ellagic acid and gallic acid were found in all cultivars, of which ellagic acid was the most abundant comprising of more than 50% of total phenolic compounds detected in each cultivar. CONCLUSIONS: The present study showed that the tested pomegranate peels exhibited strong antibacterial, antioxidant and tyrosinase-inhibition activities. These results suggest that pomegranate fruit peel could be exploited as a potential source of natural antimicrobial and antioxidant agents as well as tyrosinase inhibitors.

Concepts: Bacteria, Microbiology, Escherichia coli, Fruit, Tannin, Gram-negative bacteria, Pomegranate, Ferric

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Pomegranate (Punica granatum L.) juice (PJ) contains different types of antioxidants and bioactive polyphenols and has been reported to promote cardiovascular health through several mechanisms. The present study aimed to examine the effects of 2-week intake of fresh PJ on blood pressure, flow-mediated dilatation (FMD), serum lipid profile and concentrations of inflammatory and endothelial function biomarkers. Twenty-one hypertensive patients (aged 30-67 years) were recruited into the trial and assigned to receive either PJ (150 ml/day in a single occasion between lunch and dinner; n = 11) or the same amount of water (n = 10) for a period of 2 weeks. Systolic (SBP) and diastolic (DBP) pressures together with FMD and serum concentrations of lipid profile parameters, apolipoproteins A and B, intracellular adhesion molecule-1 (ICAM-1), vascular endothelial adhesion molecule 1 (VCAM-1), E-selectin, high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6) were measured at baseline and at the end of trial. PJ consumption was associated with significant reductions in SBP (p = 0.002) and DBP (p = 0.038) but not FMD (p > 0.05). Serum levels of VCAM-1 (p = 0.008) were significantly reduced by PJ while those of E-selectin were elevated (p = 0.039). However, no significant effect was observed from PJ on serum levels of ICAM-1, hs-CRP, lipid profile parameters, apolipoproteins and IL-6 in any of the study groups (p > 0.05). Consumption of PJ for 2 weeks has effective hypotensive effects, and may improve endothelial function by decreasing serum concentrations of VCAM-1. These findings suggest PJ as a beneficial cardioprotective supplement for hypertensive subjects. Copyright © 2013 John Wiley & Sons, Ltd.

Concepts: Inflammation, Atherosclerosis, Antioxidant, Cardiovascular disease, Blood pressure, C-reactive protein, VCAM-1, Pomegranate

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In recent years there has been increasing consumer pressure to avoid the use of agrochemicals such as chlorine on fresh plant products for extending their shelf life. The combined use of eco-sustainable techniques may be an alternative. The effect of hot water (HW), ultraviolet-C (UV-C) light and high oxygen packaging (HO) on the overall quality of fresh-cut pomegranate arils stored under modified atmosphere packaging (MAP) for up to 14 days at 5 °C was studied.

Concepts: Water, Hydrogen, Sunlight, Carbon monoxide, Modified atmosphere, Packaging, Pomegranate, Aril

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Alzheimer disease (AD) brain is characterized by extracellular plaques of amyloid β (Aβ) peptide with reactive microglia. This study aimed to determine whether a dietary intervention could attenuate microgliosis. Memory was assessed in 12-mo-old male amyloid precursor protein/presenilin 1 (APP/PS1) transgenic mice via Barnes maze testing followed by division into either a control-fed group provided free access to normal chow and water or a treatment group provided free access to normal chow and drinking water supplemented with pomegranate extract (6.25 mL/L) for 3 mo followed by repeat Barnes maze testing for both groups. Three months of pomegranate feeding decreased the path length to escape of mice compared with their initial 12-mo values (P < 0.05) and their control-fed counterparts (P < 0.05). Brains of the 3-mo study pomegranate-fed mice had lower tumor necrosis factor α (TNF-α) concentrations (P < 0.05) and lower nuclear factor of activated T-cell (NFAT) transcriptional activity (P < 0.05) compared with controls. Brains of the 3-mo pomegranate or control mice were also compared with an additional control group of 12-mo-old mice for histologic analysis. Immunocytochemistry showed that pomegranate- but not control-fed mice had attenuated microgliosis (P < 0.05) and Aβ plaque deposition (P < 0.05) compared with 12-mo-old mice. An additional behavioral study again used 12-mo-old male APP/PS1 mice tested by T-maze followed by division into a control group provided with free access to normal chow and sugar supplemented drinking water or a treatment group provided with normal chow and pomegranate extract-supplemented drinking water (6.25 mL/L) for 1 mo followed by repeat T-maze testing in both groups. One month of pomegranate feeding increased spontaneous alternations versus control-fed mice (P < 0.05). Cell culture experiments verified that 2 polyphenol components of pomegranate extract, punicalagin and ellagic acid, attenuated NFAT activity in a reporter cell line (P < 0.05) and decreased Aβ-stimulated TNF-α secretion by murine microglia (P < 0.05). These data indicate that dietary pomegranate produces brain antiinflammatory effects that may attenuate AD progression.

Concepts: Gene expression, Molecular biology, Tumor necrosis factor-alpha, Tannin, Genetically modified organism, Transgenic plant, Ice-minus bacteria, Pomegranate

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Fruits and nuts may prevent or reverse common human health conditions such as obesity, diabetes and hypertension; together, these conditions are referred to as metabolic syndrome, an increasing problem. This study has investigated the responses to ellagic acid, present in many fruits and nuts, in a diet-induced rat model of metabolic syndrome.

Concepts: Nutrition, Hypertension, Diabetes mellitus type 2, Diabetes mellitus, Obesity, Metabolic syndrome, Fruit, Pomegranate

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In the present study, the production of a reduced-sugar pomegranate juice jelly supplemented with an aqueous extract of pomegranate peel (PE) is described. Influence of different carbohydrate polymers (guar (G), xanthan (X) and tragacanth (T) gums) on rheological properties was studied. Combination GXT presented the most similar rheological behaviour to commercial jelly. Jelly (J) and jelly with PE (JE) were stored at 4°C over an 8week period for physical, chemical, antioxidant, microbiological and sensory analysis. J and JE showed similar values for °Brix, colour and Aw, though the pH of JE was lower than J. Thiol and phenolic compounds were higher in JE than in J. Antioxidant activity (radical scavenging activity and autoxidation of linoleic acid) was higher in JE than in J at 0weeks, and were decreasing with time. Pomegranate juice with additives was generally less accepted than J and JE.

Concepts: Present, Time, Antioxidant, PH, Resveratrol, Olive oil, Anthocyanin, Pomegranate

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A methanolic extract of Punica granatum (pomegranate) fruit pericarp (PGME) was tested in combination with ciprofloxacin against extended-spectrum β-lactamase (ESBL) producing Escherichia coli, Klebsiella pneumoniae, and metallo-β-lactamase (MBL) producing Pseudomonas aeruginosa, which were screened for their resistance profile against fluoroquinolone antibiotics. The minimum inhibitory concentrations (MIC) of ciprofloxacin and PGME, alone, were determined, and synergy of ciprofloxacin-PGME combinations evaluated by checkerboard assay and fractional inhibitory concentration (FIC). Nineteen out of forty-nine strains exhibited synergy with ciprofloxacin (FIC of 0.125-0.5 for ciprofloxacin) further verified by agar-well assay. This could be due to the bacterial efflux pump inhibitor (EPI) activity of the polyphenolic constituents of PGME. However, the isolates exhibiting a high level of ciprofloxacin resistance did not respond to ciprofloxacin-PGME combinations, which could be due to target site modification not influenced further by EPI activity of PGME. Again, some strains were sensitive or weakly resistant to ciprofloxacin, which exhibited ‘indifference’ to the combination, probably due to a lack of over-expressed efflux mechanism. Thus, a synergy of a ciprofloxacin-PGME combination was demonstrated for the first time against ESBL- and MBL-producing Gram-negative bacilli, and the efficacy of an existing drug improved with the help of an inexpensive alternative therapy.

Concepts: Bacteria, Antibiotic resistance, Escherichia coli, Enterobacteriaceae, Antibiotic, Fruit, Gram negative bacteria, Pomegranate

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Studies have shown that pomegranate, Punica granatum Linn. (Lythraceae), has remarkable biological and medicinal properties. However, the effects of pomegranate peel methanolic extract (PPME) on the aluminum-induced oxidative stress and histopathological change have not been reported yet. To determine the effect of PPME (200 mg/kg bwt) on the aluminum chloride (AlCl(3); 34 mg/kg bwt)-induced neurotoxicity, aluminum accumulation in brain and oxidant/antioxidant status were determined. The change of brain structure was investigated with hematoxylin and eosin, and anti-apoptosis effects of PPME were analyzed by immunohistochemistry. The present study showed an indication of carcinogenicity in the AlCl(3)-treated group representing an increase in tissue tumor markers such as tumor necrosis factor-α and angiogenin and inflammation by inducing an increase in prostaglandin E2 and prostaglandin F2α. PPME protected brain through decreasing the aluminum accumulation and stimulating antioxidant activities and anti-apoptotic proteins namely Bcl-2. Therefore, these results indicated that pomegranate peel methanolic extract could inhibit aluminum-induced oxidative stress and histopathological alternations in brain of female rats, and these effects may be related to anti-apoptotic and antioxidants activities.

Concepts: Oncology, Antioxidant, Oxidative stress, Oxidative phosphorylation, Histology, Pomegranate, Punica, Lythraceae

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Context: Several studies have reported the antioxidant activity and potential therapeutic properties of Punica granatum L. (Lythraceae) fruit. Medicinal properties have also been attributed to other parts of P. granatum tree, which are rich in bioactive phytochemicals. Objective: To explore the phytochemical characteristics, in vitro and in vivo antioxidant and in vivo antigenotoxic potential of P. granatum leaf extract (PLE). Materials and methods: The in vitro antioxidant potential of PLE was assessed by DPPH (1,1-diphenyl-2-picrylhydrazyl), ferric reducing antioxidant power (FRAP). Inhibition of lipid peroxidation (LPO) and the total phenolic content of the samples were also determined. Thirty-six male Swiss albino mice were divided into six groups (six animals each). Group 1 (control) and group 2 mice received vehicle and genotoxin alone, respectively. Groups 3, 4 and 5 were pretreated with PLE (400, 600 and 800 mg/kg body weight, respectively) prior to the administration of genotoxin. Group 6 received highest test dose of PLE. DNA damage in the bone marrow cells, hepatic LPO and antioxidants were recorded. Results: Phytochemical analysis of PLE showed the presence of flavonoids, phenols, phytosterols, tannins and carbohydrates. Aqueous PLE demonstrated free radical scavenging activity, reducing power and inhibition of LPO with the EC(50) values of 10.25, 59.88 and 20.05, respectively. A significant protective effect was observed against cyclophosphamide induced DNA damage and inhibition of hepatic LPO with concomitant increase in reduced glutathione (GSH) glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) in mice pretreated with PLE. Discussion and conclusion: PLE demonstrated a significant antioxidant and antigenotoxic potential and hence can be a potential natural source in health and medicine.

Concepts: Nutrition, Antioxidant, Bone marrow, Reactive oxygen species, Superoxide dismutase, Glutathione, Antioxidants, Pomegranate

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In this study, a waste biomass of Punica granatum L. (P. granatum L.) peels was firstly characterized by means of Brunauer-Emmett-Teller (BET) surface area, elemental analysis, FT-IR, thermogravimetric (TG) analysis and zeta potential measurement techniques. FT-IR results indicated that the mechanism involved in the biosorption of lead(II) ions and AB40 onto biosorbent was mainly attributed to lead(II) ions and dye binding of amino, carboxylic, hydroxyl and carbonyl groups. The biosorption abilities of P. granatum L. peels for lead(II) ions and Acid Blue 40 (AB40) were then investigated. Biosorption equilibrium and kinetic data fit well by the Langmuir isotherm and the pseudo-second-order kinetic models, respectively. The maximum biosorption capacities were 193.9 mg g(-1) for lead(II) ions and 138.1 mg g(-1) for AB40. Biosorption processes were spontaneous and endothermic in nature according to the thermodynamic results and the equilibrium was attained within 50 min. The validity of used kinetic models in this study can be quantitatively checked by using a normalized standard deviation Δq(%). Finally, the biosorption procedure was adopted to treat the real and simulated wastewaters including several metal salts and dyes. The wastewater applications have shown that the biosorbent indicated a reasonable biosorption capability to remove lead(II) ions (98.07%) and AB40 (94.76%) from industrial wastewaters.

Concepts: Acid, Ammonia, Temperature, Thermodynamics, Standard deviation, Dye, Standard score, Pomegranate